Turkish security forces have detained dozens of academics over a petition denouncing military operations against Kurdish rebels in the country's southeast.

Turkish media reported on January 15 that 27 academics have been accused of "terrorist propaganda" for signing a declaration titled We Won't Be A Party To This Crime, which urges Ankara to halt "its deliberate massacres and deportation of Kurdish and other peoples in the region."

More than 1,200 academics from Turkey and abroad have signed the document, prompting Turkish prosecutors to launch an investigation into the signatories for "insulting the state" and engaging in "terrorist propaganda" by signing the declaration.

Southeastern Turkey has seen violent clashes between separatists of the Kurdistan Workers Party (PKK) and the Turkish military since a cease-fire between the sides collapsed in July.

Human rights activists say dozens of civilians have lost their lives in areas under curfew.

The majority of the January 15 detentions were in the western industrial province of Kocaeli, near Istanbul, according to local media reports.

Later in the day, 15 of the detained academics were released after questioning, Turkey's state-run Anadolu Agency reported.

Turkish prosecutors' actions drew criticism from both the opposition and the U.S. ambassador in Istanbul, John Bass.

"While we may not agree with the opinions expressed by those academics, we are nevertheless concerned about this pressure having a chilling effect on legitimate political discourse," Bass said in a January 15 statement on the U.S. Embassy's Twitter feed.

Speaking after Friday Prayers, Turkish President Recep Tayyip Erdogan denounced the petition's signatories, saying that those who did not want to do politics in parliament "should go dig trenches or go to the mountains" -- a reference to the tactics used by the PKK.

The declaration, published on January 11, accuses Erdogan's government of heavy-handedness in its efforts against militants.

"The right to life, liberty, and security, and in particular the prohibition of torture and ill-treatment protected by the constitution and international conventions have been violated," it states.

"We demand that the state abandon its deliberate massacre," the declaration adds.